Stationary induction apparatus



T. C. LENNOX STATI ONARY INDUCTION APPARATUS Filed Oct. 26, 1920 2Sheets-Sheet 1 Inventor:

Tho as C.Lenn ox,

His/Attorney Jan. 13, 192s. 7 1,523,378

'r. c. LENNOX STATIONARY INDUCTION APPARATUS Filed Oct. 26, 1920 2Sheets-Shoot 2 Inventor;

Tho s C.L.ennox,

H is Attorney.

Patented Jan. 13, 1925.

. UNITED STATES 1,523,378 PATENT OFFICE.

THOMAS C. Lmmox, or rrrrsrmrn, MASSACHUSETTS, assmnoa 'ro GENERAL ELEG-rarc COMPANY, A CORPORATION or NEW YORK.

STATIONARY INDUCTION APPARATUS.

Application filed October 26, 1920. Serial m5. 419,662.

To all whom it may concern:

Be it known that I, THOMAS C. LENNOX, a subject of the King of GreatBritain, residing atPittsfield, State of Massachusetts,

6 have invented certain new and useful Improvements in StationaryInduction Apparatus, of which the following is a specification.

My invention relates to stationary induc- 1 tion apparatus,-such astransformers, some reactors, and the like, which are cooled by thecirculation of air over the windings and has for its object an improvedarrangement of parts which is readily manufactured and adapted forquickly and efiicaciously cooling the windings.

In transformers and the like of the shell type, it has been the practiceto dispose the windings in vertical planes, which construc- 20 tionreadily lent itself to the circulation of air currents upwardly betweenthe windings. Where, however, in order to get better magnetic balance inthe respective parts of the coils, a circular construction is em- 25ployed, mechanical considerations for securing the parts together notinfrequently lead to a core type construction with horizontally disposeddisc-coils. The methods heretofore employed in shell type constructionsfor effooting the circulation of air over the windings are not at alladapted to effecting a circulation of air without pockets overhorizontally disposed disc-coil windings. It is with this latter type ofwinding that my invention is chiefly concerned.

In the practice of my invention, I have provided a novel arrangement ofbafiles which causes the air or other similar cooling medium to traversealternate inwardly and outwardly radially disposed paths and therebycool by convection substantially the whole of the adjacentlydisposed'surfaces of each of the disc-coils comprising a winding of thistype.

For a more complete understanding of the nature and objects of myinvention, reference should be had to the following detailed descriptiontaken in connection with the accompanying drawings in 1 which:

and Fig. 2 a vertical section of a transformer constructed to embody myinvention; while Figs. 3 and 4 show details of certain baiile platesemployed in the construction disclosed in Figs. 1 and 2.-

Fig. 1 is a plan view partly in section Referring now to the drawings,denotes a core of laminated magnetic material, on each leg 11 of whichis mounted an interleaved disc-coil winding 12. The coils are themselvesheld in proper spaced relation by means of insulating collars 13 andradially disposed spacing devices 14 which latter also are made ofinsulating material. This spaced 'coil stack is itself insulated fromthe core by means of insulating cylinder 15.

It will be understood that in transformer construction, to which myinvention is particularly applicable, the coils comprising windings 12are suitably connected and arranged in high and low voltage groups; thecollars 13 generally being disposed between such groups.

The core 10 with its windings is surrounded by a casing 20, and placed,when installed, over a pit or air chamber, as indicated at 21 in Fig. 2.This pit 21 is adapted to receive a. constant supplyof air from aconvenient source, such as a fan (not shown), which source communicateswith the pit through the passage 22; the pit being adapted to dischargeinto the casing through one or more openings, such as are shown at 23.The casing 20 has a cover 24 provided with valves 25 adapted to controlthe passage of air therethrough.

To direct properly the passage of the air through the casing and overthe windings, baflling means are employed according to my invention. Atop bafile plate (a plan view of which is shown in Fig. 3) has itscentral portion cut away as at 31 so as to fit down over the top portionof the core 10. The peripheral portion of this baflie has a plurality ofdeep recesses or openings cut therein, as indicated at 32 but otherwiseis shaped to conform with the contour of the casing 20. The projectingportions 33 of the baffle 30 which remain between the recesses,accordingly make a snug fit against the interior sides of the casing 20.

In addition to having the centralportion of baflle 30 cut away to fitover the core, it has the end portions of the opening 31 each cut tohave a circular contour that will 00- incide with the end of aninsulating cylinder 15 inorder to permit the egress of air from betweenthe-core and the cylinder.

A similar bailie late 35 (a plan view of which is shown in ig. 4) is cutto fit over the bottom portion of the core 10. This baffle is formed tofit against the sides of the with the lower ends of cylinders 15,thereby permitting a current of air freely to enter the space betweenthe core and cylinder from the air pit 21.

When the baffle plates and are in place, it is seen that theiropeningsor recesses are in staggered relation. 'In-order, however, toforce the air entering an opening or recess in the lower baffle plate topass over the coil faces before making egress through an opening orrecess in the upper balfie-plate,*I arrange a number of vertical baflieplates 40, generally radially disposed about the winding stac s topartition off the spaces over-the recesses in the lower baffle platefrom those'under the recesses in the upper plate.

The vertical bafiie plates 40 are notched along the inner edges, asshown at 41, soas to fit over the collars 13. This inner edge ofeachfbaflle 40 is otherwise straight and preferably fitssnugly againstthe edges of the coils of windings 12 between the spacing devices 14. g

From this construction, it ,is seen thatv air i or other cooling mediumfrom the pit 21 in passing up through the openings in the lower baflieplate, enters a channel with a closed upper end. To find egress the airin such channel is compelled to pass about the edges of the verticalbafiies 40 along the side andthence intgwthe adjacent channels whichhave been partitioned off and provided with closed lower-ends butwithopen upper ends by reason of the staggered relation of the openingsemployed in the baf fie plates 30 and 35. This .passage of the airfollows generally radial directions inwardly and outwardly over thefaces of the coils and about the edgesof the baflies 40,

which movement has been indicated by the arrows a in Fig. 1; the spacingdevices 14 serving in this connection as baflies or .de-

flectors to facilitate this radial-movement.

It will be observed that the .air currents thus moving over the coilfaces 'do not pass in succession over the various coils but pass inparallel streams thereover thus permitting a large volume of air to bequicklyand freely circulated through the windings and therebyapproaching a substantially maxi mum cooling effect with a given volumeof air. The volume of air passing and hence shown nor restricted in thechoice of recog-' nized equivalents except as defined in my claimshereunto appended.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is 1. An electrical apparatus comprising windings enclosed in acasing and arranged in spaced relation along a rectilinear Winding axis,and baflling plates extending outwardly from the spaces between saidwindings and separating the space surrounding said windings-into aplurality of channels, said channels being provided alternately withentrance and exit openings-for a cool ing medium, whereby acoolingmedium sup plied through said entrance'openings is conducted to and fromthe spaces between said windings and about the inner edges of saidbaflling plates.

2. An electrical apparatus comprising disc-coil windings arranged inspaced relation along a rectilinear winding axis, asurrounding casing,baflie plates disposed withm said casing parallel to the planes of saidwmdmgs and above and below the same, said plates being provided withstaggered openings about their peripheries, and radial baffle platesdisposed between said first named baflie plates and arranged about saidwindings in a manner to partition off the spaces below and above saidopenings whereby a cooling medium enterlng an opening in one of thefirst named bafiie lates will move 1n parallel streams about t e edge ofa radial baffle, plate traversing the spaces between said windings tofind egress through an opening in another of the first namedbaflieplates.

3. In transformers and the like, the combination' with a core, ofhorizontally disposed disc-coils arranged in spaced relation on a leg ofthe same, a casing surrounding the core and coils, horizontal bafileplates fitted over said core above and below said coils and providedwith openings about their peripheries arranged in staggered relation,and vertical baflle plates disposed between said horizontal ba'flleplates in radial ar rangement' about said coils and placed so as topartition ofl the spaces respectively below and above the openings insaid horizontal baflie plates. 1

In" witness whereof, I have hereunto set my hand this 22nd day of Oct.1920.

THOMAS C. LENNOX.

